Variable ND filters - anyone uses?

[Deleted member 88956]

As I'm looking for a set of ND filters, came across variable ones. Some appear to have a rather large range. This is to be used mainly for film shooting.

Anyone uses them, any recommended make?

 

[Maris]

Here's one I posted earlier:
I have and use a "Fader" variable ND filter that is made of two polarisers that can be turned against each other.
Not all wavelengths of light are equally attenuated so there is a slight colour cast introduced. I use black and white films so it's not a problem for me.
The ND effect is not precisely even over the field of view at strong attenuation values. This depends on luck and the individual quality of a "Fader".
A variable density filter depending on polarisers is still a polariser and the usual limitations apply; uneven wide-angle skies for example.
Near maximum attenuation values the dreaded "black cross" effect may be seen. This is caused by oblique rays not being extinguished the same amount as normal incidence rays.
My Fader is rated up to 10 stops ND but I don't set it beyond 5 stops to avoid the optical nasties that I can't really see through the dark viewfinder of my reflex camera.

 

[Deleted member 88956]

Thanks. Are you also saying to drop convenience and get dedicated fixed ND instead?

 

[Sirius Glass]

Polarizor do not do the same thing as ND filters. Polarizors work on light coming in at certain orientations and the angle of the sun light. ND filters darken uniformly. ND2 darkens two f/stops. ND3 darkens three f/stops. Variable ND filters darken across a range of f/stops. The first questions are what do you need a ND filter for and why, not how many can one buy. In over sixty years of photography I cannot remember even one time that an ND filter was necessary. So start with your reason(s) and then we can help you find the answer.

 

[DREW WILEY]

I'd think there would be a fair amount of qualitative loss, fine detail wise, using those things. Strong ND filters have caught on because lots of digital cameras do not have a low ASA option, and need to be slowed down for certain kinds of shots, like flowing water or blurred ocean waves.

In landscape work, gradational ND's became a fad for trying to control overexposure of the sky relative to the foreground, especially with color chrome films. Galen Rowell popularized them, and the Sing-Ray series even used his name for marketing theirs. But every single one of his own shots I've ever seen that relied that looked like it - distinctly fake tonality and color, and overall, kitchy, touristy. Sometimes a reflection in a foreground stream or pond was even more intensely colored that the sunset sky about it - a dead giveaway. I've never used these, and never will. But if someone were really careful with them, well, maybe... I just find it a detour or clumsy trick in lieu of really understanding specific films and lighting situations.

 

[Deleted member 88956]

Polarizor do not do the same thing as ND filters. Polarizors work on light coming in at certain orientations and the angle of the sun light. ND filters darken uniformly. ND2 darkens two f/stops. ND3 darkens three f/stops. Variable ND filters darken across a range of f/stops. The first questions are what do you need a ND filter for and why, not how many can one buy. In over sixty years of photography I cannot remember even one time that an ND filter was necessary. So start with your reason(s) and then we can help you find the answer.

Reasons are simple, use it to slow down shutter for special effects (let me just say shoot a highway with high traffic that comes out car free). I did not think this was a subject of my question.

VD ND filters are marketed, some by rather well known brands. But @Maris has brought an important point. I never looked into how they were made to limit light. I think I'm already straight onto getting fixed values as they were meant to be.

 

[Sirius Glass]

Reasons are simple, use it to slow down shutter for special effects (let me just say shoot a highway with high traffic that comes out car free). I did not think this was a subject of my question.

VD ND filters are marketed, some by rather well known brands. But @Maris has brought an important point. I never looked into how they were made to limit light. I think I'm already straight onto getting fixed values as they were meant to be.

The OP was asking a question which sounded as though "I see one but there are a whole bunch I could buy. Which ones should I buy?" The first thing is to find out what the OP wants to do, not what you want to do, which is well thought out but has nothing to do with this particular OP.

 

[Deleted member 88956]

The OP was asking a question which sounded as though "I see one but there are a whole bunch I could buy. Which ones should I buy?" The first thing is to find out what the OP wants to do, not what you want to do, which is well thought out but has nothing to do with this particular OP.

The OP was asking about user feedback on VD ND filters. It makes no difference what it is to be used for.

 

[DREW WILEY]

Of course it makes a difference! A big difference! For one thing - if a person if trying to pick one of these for color film usage, versus just black and white film, the lack of pure color neutrality in some people's experience might be a significant factor indeed, needing to be pointed out relative to that very kind of application. Specific intended usage is ALWAYS an important factor best stated or otherwise asked right up front. Or if with reference to a wide angle lens usage difficult to shade, it would involve reflectivity of the surface coatings, and potential flare, versus a well shaded longer lens application. Yet again, if used in cold damp weather or humid tropical conditions, that should should be asked, because it potentially becomes a problem with any compound filter, especially polarizers, due to the risk of trapped moisture between the elements, requiring a special kind of supplementary seal to minimize that risk.

 

[pentaxuser]

Anyone uses them, any recommended make?

Drew, isn't this the key question that the OP wants us to concentrate on? He is looking for answers from those who have used variable ND. Of the replies so far only Maris' experience and reply would seem to meet his requirements.

pentaxuser

 

[DREW WILEY]

That just shows you how few use them, or else if they do, how few really understand them. I'd be talking to an actual optical engineer first, or engineer behind the specific company making them if it were me, not seeking random opinions. Go to the horse's mouth. And in that case, specific application means EVERYTHING. Want specific answers? Ask specific questions. But people have to begin somewhere, so understand what is going on in this particular case.

 

[btaylor]

I don’t think you need to be an optical engineer to understand that a so-called variable ND is 2 polarizing filters attached to each other. And there is the rub- a “variable ND” is kind of a misnomer, because an ND filter is supposed to cut light intensity and nothing else (I know some are more neutral than others, but that isn’t the point here). You’re going to get at least some polarizing effect with the variable ND, whether that bothers you or not is up to you. They are convenient, lots of people buy them. Personally I will stick with real ND filters.

 

[AgX]

Strictly speaking one is even getting two polarizing effects.

 

[Deleted member 88956]

I don’t think you need to be an optical engineer to understand that a so-called variable ND is 2 polarizing filters attached to each other.

As title song of the Couplings states ... Perhaps, Perhaps, Perhaps.

Not everything is crystal clear at first sight. Sometimes it's good to know what is behind it, sometimes the opposite is true. I knew adding vinegar to water when boiling eggs helps, and slept well with it, but only later did I find out why it does. Still use vinegar, but now I boil eggs like a scientist. They still taste the same though.

 

[Jim Jones]

For photographing solar eclipses or Venus transits across the sun I've used variable density filters and/or a stack of roughly complementary filters. The black cross problem Maris mentioned in post #2 was obvious when using a variable ND filter or ordinary crossed polarizing filters for much attenuation. Stacking filters introduces several surfaces that can contribute to poor image quality. Filters are like medicine: good when necessary, but best avoided otherwise. However, in adverse conditions, a UV filter might help protect the front lens surface. I prefer unobstructed image quality over lens protection and did have to retire a favorite Summicron after decades of hard use without a protective filter. It seems like a reasonable sacrifice.

 

[DREW WILEY]

Everybody should know by know that photographic polarizing filters themselves vary widely in quality item to item, brand to brand. And the fact that most of the folks thinking about variable density ones happen to be shooting small format cameras means that any qualitative loss due to these (and it will be there) is going to have a disproportionate effect overall to image quality. Jim just hit the nail on the head - it's the same kind of issue as stacking filters. The more the air/glass interfaces involved, the more the potential loss, especially if you've opted for a cheaper variety of filter with less effective coatings.

If you can afford to try one of everything, have at it. I prefer to do some actual homework first before dropping money.

 

[benveniste]

I have a Marumi DHG VARI ND2-400 in 77mm. Here are a few general comments about it.

-- Like all variable ND filters, it works via cross polarization. In effect, it's two circular polarizers placed face-to-face. So you will not see the same effect as you would with a standard polarizer.
-- Color shift with any actual filter, even a UV filter, is a reality. Marumi polarizers tend to transmit a little less green than blue or red. So if you need to color match with and without a filter, you'll find it hard to do so.
-- For any polarizer, the degree of polarization depends on the angle to the light source. This causes uneven exposure, which is especially noticeable on sky shots with wide angle lenses. For sky shots with a variable ND filter, you can get an ugly "X" exposure pattern. At high ND settings, you may even be able to detect the pattern on 35mm film with a 50mm lens.

As a result, I've used the Marumi less than I thought I would. We'll see if that changes once the pandemic passes and I'm shooting more.

 

[Sirius Glass]

I have a Marumi DHG VARI ND2-400 in 77mm. Here are a few general comments about it.

-- Like all variable ND filters, it works via cross polarization. In effect, it's two circular polarizers placed face-to-face. So you will not see the same effect as you would with a standard polarizer.
-- Color shift with any actual filter, even a UV filter, is a reality. Marumi polarizers tend to transmit a little less green than blue or red. So if you need to color match with and without a filter, you'll find it hard to do so.
-- For any polarizer, the degree of polarization depend on the angle to the light source. This causes uneven exposure, which is especially noticeable on sky shots with wide angle lenses. For sky shots with a variable ND filter, you can get an ugly "X" exposure pattern. At high ND settings, you may even be able to detect the pattern on 35mm film with a 50mm lens.

As a result, I've used the Marumi less than I thought I would. We'll see if that changes once the pandemic passes and I'm shooting more.

i recommend that the OP save money that would be spent on a variable ND filter and instead buy several fixed ND filters of various strengths.

 

[DonW]

I use a VR ND filter quite a bit for both video and still work. Works like a charm. If I NEED 3.6ND I can get exactly what I need.

I also use fixed graduated ND filters. So I'm sure to go to hell!

 

[MattKing]

So I'm sure to go to hell!

You forgot to add the emoticons

 

[jtk]

I use a VR ND filter quite a bit for both video and still work. Works like a charm. If I NEED 3.6ND I can get exactly what I need.

I also use fixed graduated ND filters. So I'm sure to go to hell!

Same experience...used an extreme 72 mm grad that I had custom made by Lee (great Britain) for a group of lighting tricky 4×5 chrome shots, subsequently found all sorts of uses with Kodachrome in SW desert . Now that I think about it...if I can find it it might work great with DSLR.